4.5" x 20" Water Softening Filter Cartridges for Filter Housing AMI Home Water Softener Filter cartridges remove minerals through an ion exchange process. Designed for point of use softening, these cartridges are ideal to provide soft water to a single appliance, ice or beverage machine, or other equipment. - Cartridge Dimensions: 4.25"O.D. × 20"L - Softening Cartridge Model Number: H-F4220SOFT - For Filter Housing: Designed to fit 20" Filter Housing (housing outer dimensions approximately 7.5" OD × 23"H.) - Softening Capacity: 4500 Grains of Hardness - Maximum Flow: 1.5 GPM How do Water Softener Cartridges work? Hard Water contains dissolved minerals in the form of Calcium (Ca), Magnesium (Mg), and Iron (Fe). Removal of these minerals is accomplished by softening the water through an ion exchange process using water softening filter cartridge. As the water flows through the resin in the filter cartridge, the dissolved minerals become attached to the resin, creating soft water. Removing hardness from water can prevent hard water scaling and staining, and prolongs the life of RO membranes if used for pretreatment to an RO System. Use Water Softening Cartridges for: - Point of Use Water Softening - Pretreatment Home RO Systems - Inline Hose Canisters for At-Home Car Washing - Espresso Machines - Ice Makers - Washing Machines - Medical Equipment - Laboratory - Low Volume Beverage and Food Service - Soft Water for Appliances ...and more!